Abstract: Method for detecting a defective node which is connected to a bus, the node incrementing an internal error counter in a normal operating state when an error is detected, and the node switching to an isolated operating state, in which the node does not exchange any messages via the bus if the internal error counter of the node exceeds a predetermined error threshold value, and the node switching from the isolated operating state to the normal operating state when a condition is fulfilled and that change in state being detected, and the node being detected as being defective if a rate of the detected state changes exceeds an adjustable change rate or a number of detected state changes exceeds an adjustable state change threshold value.